Why this game is intriguing: Even without that new quarterback in Denver, this would be a great game, watching Ben Roethlisberger take on a rabid Broncos pass rush. But yes, it's Peyton Manning's Mile-High debut that really takes this contest to another stratosphere. The long-time Indianapolis Colts star is back after sitting out a season, and all those questions from the preseason -- Can he take a hit? Does he still have the necessary arm strength? -- will be answered. Finally, we can really see for ourselves. The training wheels come off.
What to watch: We already covered the biggest thing. How does Manning look in a new uniform, with a new offense, in a new reality? The fact that Peyton's debut comes against a vicious defense will only make it more telling. But Pittsburgh has plenty of storylines to follow, too. Do they run the ball 40 times under new offensive coordinator Todd Haley? Is Mike Wallace ready to roll after a lengthy contract dispute? His ability to stretch the field impacts the entire offense.